Mealy Rosella or Pale-headed Rosella: Mutations, Breeding
Mealy Rosella (Platycercus adscitus) or Pale-headed Rosella
Description:
The Mealy Rosella is a sub-species of the Blue-cheeked rosella (Platycercus adscitcus adscitcus). As far as I know, there are no pure breeding pairs of the nominate species, the Blue-cheeked Rosella, in South Africa and no other sub-species.
Behaviour in the wild Mealy Rosella is distributed over a large area in the Northeast of Australia. Their numbers have been greatly reduced, mainly as a result of bush eradication as the mature trees were used as nest sites for the Rosellas. In the wild, the majority of their food consists of Indigenous Australian grasses as well as the seed of imported grasses.
To this diet, they add berries and fruits of indigenous trees and shrubs. They also eat the buds of sprouting trees and shrubs, flowers, and nectar, as well as insects and their larvae.
The Mealy Rosella seldom damage, if ever, planted crops. In the wild, they breed early in Spring, from August to November. The nests are usually in the hollow trunks or branches of trees that are usually nearby a perennial river or other perennial water source. There are, however, documented incidents of them nesting in tunnels in riverbanks. Where the nests are in trees, they can be from two to ten metres off the ground. The depth of the nest varies from 48cm to 120cm, usually with a diameter of 180mm.
Mealy Rosella in our aviaries:
The difference in the sexes is not always obvious. It is therefore better to have the birds surgically or DNA sexed. In Europe, where all our Mealys come from, the two subspecies were interbred indiscriminately, so there have not been many pure Blue cheeked Mealys available for many years. However, the Mealys in South Africa are just about pure sub-species. These birds come into full colour between fourteen and eighteen months of age, and will usually breed in their second year. Amongst young Mealys there are often rust-red flecks on their head. These disappear when the birds moult into their mature feather.
Measurements and weights:
Average length: 32cm
Average weight: males 130g.
females 115g
Ring size: 5.5mm (PASA code D)
FEEDING:
Because they are seed eaters, like most Australian parakeets, feeding is relatively easy. The micronized grain mixtures that are commercially available work extremely well as basis. To this I simply add grated and chopped greens such as carrots, beetroot, pumpkin, or sweet potato.
I would like to urge breeders not to add any further protein, vitamin, or mineral concentrates to this mixture. All the commercially available micronized mixtures that I know of have a complete range of vitamin, protein, and minerals already added. All that you will achieve is to make the food dangerously high in certain minerals and vitamins, and this could be bad for your birds.
I feed the mixture in the early mornings and then after breakfast, each aviary gets 20g of fine seed consisting of millet, canary seed, and manna. In the afternoon, each aviary gets 30g of sprouted sunflower. I never add any chopped fruit to my food for Australian parakeets. Fruit contains more than 90% water and sugars that attract bees to the food and cause the food to ferment, while the feeding value of the fruit is relatively low.
BREEDING:
As a said earlier, these birds breed in hollow tree trunks and branches. It would be an advantage for breeders to remember this. The shallowest nests should be approximately 50cm deep, so don’t give your Mealy Rosella a cockatiel nest box and expect that they will immediately accept it. Rather give them a nest that’s at least 50cm deep and 20cm x 20cm in cross-section. About 20cm x 20cm is ideal with an entrance of 65mm in diameter.
When the cross-section of the nest is too big, the females feel exposed when breeding, and will always pull eggs into a corner and may roll them from one corner to another for safety. In this process, the eggs can be broken or damaged in other ways. We still find that the biggest mistake made by potential breeders is not making the nest deep enough or making the diameter too large.
Same Mealy Rosellas will still break eggs. First try a smaller diameter, e.g., 18cm x 18cm, or a deeper nest. If this doesn’t work, then use foster parents.
Red rumps make ideal foster parents. Test the foster parents first however to make sure that they are rearing their babies well before you give them the more expensive eggs.
The Opaline Mutation:
As with all opaline mutations, the inheritance of the opaline gene is sex-linked. Sex-linked mutations work as follows:
The male has two X chromosomes, but the female has only one. With the female, the second chromosome of the two is a Y, so her chromosomes are X and Y. the Y chromosome is too small to carry a significant gene. That means that the female is either normal or otherwise opaline, she is not a carrier, while the male needs two X chromosomes to show opaline, and if he has only one chromosome with the opaline mutation, he is a carrier.
That means that none of the opaline females’ daughters can be opaline. Whenever a chick inherits an X chromosome from its mother it means that it will always be a male. In other words, females can only carry sex-linked mutations to their sons, whereas a male can carry a sex-linked mutation to either his daughter or son. The following table will indicate what can be expected with the various combinations.
Breeding results:
Opaline male X Normal female
Normal/opaline male + Opaline females
Normal male X Opaline female
Normal/opaline males + Normal females
Normal/opaline male X Normal female
Normal males + Normal/opaline males +
Normal females + Opaline females
Normal/opaline male X Opaline female
Normal/opaline males + opaline males +
normal females + opaline females
Opaline male X Opaline female
Opaline males + Opaline females
Mealy Rosella conclusion:
As far as I know the opaline is the second mutation to be established. The other mutation is cinnamon, (also sex-linked), that does not make me terribly excited. Cinnamon dilutes the general colour of the Mealy, making this a not so interesting colour mutation. Opaline, however, is altogether different. As can be seen in the photographs, the opaline is a believably beautiful bird. One of the results of the opaline mutation is that it increases the amount of red in a bird. While the red in the mealy is severely reduced, the head is almost free of red in pure mealys.
I have seen “opaline mealys” that had almost totally redheads. In these pairs, the split mealy males usually give the secret away because the golden mantle gene has been used to develop the red on the head and the chest. My advice is to stay away from any bird where the split males have any red, except under the tail feathers. (Platycercus adscitus)
Further reading about Rosellas and their mutations:
Crimson Pennant Rosella: Pastel Mutations
Stanley Rosella: Breeding, Feeding, Cage and Nest Box
